Computer System Components PDF

Computer System Components BICT 1102 Introduction to ICTs 1/51 Outline  Computer System Unit  Hardware Components: ► Central Processing Unit (CPU): ALU, CU, and Registers ► Storage: Primary (RAM, ROM, Virtual, Cache) and Secondary (HDD, SSD) ► Input...

Computer System Components BICT 1102 Introduction to ICTs 1/51 Outline  Computer System Unit  Hardware Components: ► Central Processing Unit (CPU): ALU, CU, and Registers ► Storage: Primary (RAM, ROM, Virtual, Cache) and Secondary (HDD, SSD) ► Input Devices: Keyboard, Mouse, Joysticks, etc. ► Output Devices: Monitors, VDU, Printers  Software: ► Application Software ► System Software Daeyang University BICT 1102 2/51 Introduction to ICTs 2/50 Computer Functional Units  A computer consists of five functionally independent main parts: input, memory, arithmetic and logic, output, and control units Daeyang University BICT 1102 3/51 Introduction to ICTs 3/50 Inside the System Unit  The system unit is a case that contains computer electronic components that process data. Also called the chassis Daeyang University  Main components on motherboard include processor (CPU) and memory BICT 1102 4/51 Introduction to ICTs 4/50 Inside the System Unit Motherboard (1/2)  It is the main circuit board inside system unit, also called System Board  Some units are soldered, nonremovable Daeyang University  Sockets for removable units: Microprocessor and RAM chips, various expansion cards BICT 1102 5/51 Introduction to ICTs 5/50 Inside the System Unit Motherboard (2/2)  Removable components allows expand or upgrade a system  Expansion: adding hardware, increasing a computer’s capabilities for performing tasks beyond basic system scope ► For instance, add video and sound cards for better gaming experience  Upgrading means changing to newer, usually more powerful or sophisticated versions, such as a more powerful microprocessor or more memory chips Daeyang University BICT 1102 6/51 Introduction to ICTs 6/50 Central Processing Unit (CPU)  As the “brain” of a computer, the CPU performs calculations, executes instructions, and processes data.  Manipulates data into information based on software instructions.  It works with other circuits such as main memory. Daeyang University  Every task or operation on a computer, e.g., typing, running apps, or browsing the web, is managed by the CPU. BICT 1102 7/51 Introduction to ICTs 7/50 Central Processing Unit (CPU)  Key functions ► Fetch: Retrieves instructions from memory. ► Decode: Interprets instructions to understand the required action. ► Execute: Performs calculations or operations based on the instructions. ► Store: Saves the results back to memory if needed.  Example: When using a calculator on your computer, the CPU interprets and performs the calculations you enter ► E.g., 5 + 3 = 8 Daeyang University BICT 1102 8/51 Introduction to ICTs 8/50  Central Processing Unit (CPU)  Main parts of CPU: ► Arithmetic and Logic Unit (ALU): performs operations on data, e.g., addition ► Control Unit: Coordinates activities within the machine ► Register Unit: Comprises storage cells (registers) for temporarily storing information within the CPU Bus: A collection of wires that connects CPU and RAM Daeyang University BICT 1102 9/51 Introduction to ICTs 9/50 Central Processing Unit (CPU) Control Unit (CU) & The Machine Cycle  It also decodes and executes each instruction stored in CPU  Controls movement of electronic signals between: ► Main memory and ALU ► Main memory and the input and output devices  For every instruction, CU executes four basic machine cycle operations Daeyang University BICT 1102 10/51 Introduction to ICTs 10/50 The Central Processing Unit (CPU) Program Execution – Machine Cycle  For every instruction, CU executes four basic machine cycle operations: (1) Fetch, (2) Decode, (3) Execute, (4) Store Daeyang University BICT 1102 11/51 Introduction to ICTs 11/50 Central Processing Unit (CPU) The Arithmetic and Logic Unit  The Arithmetic and Logic Unit (ALU) performs arithmetic and logical operations and controls the speed of those operations  Arithmetic operations are the fundamental math operations: addition, subtraction, multiplication, and division  Logical operations are comparisons, thus the ALU compares two pieces, A:20 and B:10, of data are: ► Equal to (=), e.g., A = B (Answer: ?) ► Greater than (>), e.g., A > B (Answer: ?) ► Greater than or equal to (≥), e.g., A ≥ B (Answer: ?) ► Less than (